This invention relates to a photographic camera, especially a very small camera of the kind often called a sub-miniature camera, having a handle or manually operated member which is movable from a basic rest position in a direction transversely of the optical axis of the camera, for the purpose of winding the film and tensioning or cocking the shutter. This handle or manually operable member is operatively connected with a rack which is displaceable in the same direction, and which drives a film winding shaft directly or indirectly. In addition, there is a cover plate or blind plate coupled with the manually operable handle for covering and clearing the camera lens or the camera viewfinder or both.
In known cameras of this kind, the camera housing is made in two parts telescopically extensible and retractable relative to each other, in a direction transversely of the optical axis. The function of the cover plate for covering or uncovering the lens opening is here taken over by the telescopically movable part of the camera housing. Secured to this movable part of the housing is a rack which actuates the shutter tensioning or cocking mechanism and also, through a gearing, operates the film winding shaft. This gearing (in the known camera being discussed) is formed as differential gearing, especially as planet wheel gearing, so designed as to permit uncoupling the film winding shaft from the gearing when the film has been fed to proper position, so that the rack in engagement with the gearing is freely movable after the film has been properly fed. With this arrangement, the camera can again be opened out or closed up as desired, without causing further winding of the film or displacement thereof.
Such planet wheel gearing, as used in the prior camera mentioned, not only is expensive to manufacture, but also takes up considerable space, if the gearing is designed and constructed in an operationally reliable manner. These factors make such gearing unsuitable for use in very small cameras with a minimum cross section which is, for example, only very slightly greater than the cross section of the film chamber of an ordinary commercial film cassette of the 110 size.
The present invention is based on the problem of producing satisfactory and reliable gearing for the film winding and shutter tensioning operations, in a form which is quite shallow and space-saving, suitable for use in a camera with minimum cross-section dimensions, in which in the usual way the camera lens and camera viewfinder can be covered and cleared or uncovered as desired, independently of the film winding and shutter tensioning operations, by actuation of the drive element for the gearing. Furthermore, the invention takes into account the fact that such gearing must be able to be produced in an economical or cost-saving manner.
According to the present invention, this problem is solved by providing, in a camera otherwise of the kind above described, a connection between the handle or manually operable member, and the rack, which connection is automatically eliminated or rendered inoperative in the basic or rest position of the handle after a film winding operation has taken place if the shutter release has not taken place.
According to a further development of the invention, for this purpose the rack is guided for longitudinal displacement, and in the basic or rest position of the handle, the rack is swingable about a pivot point. The handle is operatively connected to the rack in a shape locking or form locking manner, for longitudinal movement with each other, and this operative connection can be disconnected or rendered inoperative by pivoting or swinging the rack about its pivot point.
In a preferred embodiment of the invention, the pivot of the rack is at one end of the elongated rack, and there is a recess or notch at the other end of the rack. A hooklike projection on the handle member or manually operable member extends into this notch in the rack when the handle and the rack are operatively connected, and the hook on the handle is not engaged in the notch of the rack when the rack is pivoted to its disengaged position.
According to a further development of the invention, the swinging of the rack on its pivot is brought about by a device which is controlled by a feeler lever which is responsive to the position of the film. In a camera designed for use with perforated film, where the perforation intervals correspond to one picture step or "frame," the rack pivoting device is normally in an inoperative position, and is moved into its operative position by the dropping of the feeler lever into a film perforation, thereby rendering the rack pivoting device operative to swing the rack to disconnect it from the manually operable handle. When the shutter release is operated to make an exposure, this lifts the feeler lever out of the perforation in the film, thus rendering the rack pivoting device inoperative again so that the rack again becomes operatively connected to the manually operable handle. Thus during the time interval between the completion of the film winding operation and the actuation of the shutter release, the rack which serves to drive the film winding operation and to tension the shutter remains operatively disconnected from the manually movable handle, which means that during this time interval the handle may be moved back and forth as often as desired, to close or to open the lens window and the viewfinder window, without causing any further movement of or damage to the film or the shutter tensioning mechanism.
The design according to the present invention has the important advantage that all gearing parts such as the rack, the manually movable handle, the rack pivoting device, and all individual elements and feeler levers, can be produced with the requisite precision from synthetic plastic material, considerably reducing the manufacturing cost thereof.